Popular smoking articles such as cigarettes have a substantially cylindrical rod shaped structure and include a charge of smokable material such as shredded tobacco (e.g., cut filler) surrounded by a paper wrapper thereby forming a so-called “tobacco rod.” It has become desirable to manufacture cigarettes having cylindrical filter elements aligned in an end-to-end relationship with the tobacco rod. Typically, filter elements are manufactured from fibrous materials such as cellulose acetate and plug wrap, and are attached to the tobacco rod using a circumscribing tipping material. Such cigarettes having filter elements are referred to as “filter cigarettes.”
Filter cigarettes conventionally have been sold in packages, each package normally containing twenty (20) cigarettes. Typical cigarette packages have a generally rectangular parallelepiped form. One type of popular cigarette package employs a container having the form of a so-called “hard pack,” “crush proof box” or “hinged lid package.” See, for example, U.S. Pat. No. 3,874,581 to Fox et al.; U.S. Pat. No. 3,944,066 to Niepmann; and, U.S. Pat. No. 4,852,734 to Allen et al.; as well as European Pat. 0392737 to Moeller, and U.S. Pub. Pat. App. No. 2008/0230410 to Jones et al., each of which is incorporated herein by reference. Another type of popular cigarette package employs a container having the form of the so-called “soft pack.” See, for example, U.S. Pat. No. 3,695,422 to Tripodi; U.S. Pat. No. 4,717,017 to Sprinkel, Jr., et al.; and, U.S. Pat. No. 5,333,729 to Wolfe; each of which is incorporated herein by reference. Both types of cigarette packages are normally packed in cartons also of generally rectangular parallelepiped form, typically ten (10) packages to a carton.
These conventional cigarette packages are generally configured to maintain the freshness and moisture content of the cigarettes and to protect the cigarettes from adverse environmental conditions that could degrade their freshness and quality. Such conventional cigarette packages typically comprise three separate wrappings: (1) an inner foil liner comprising a metal foil laminated to a paper substrate or a metallized paper which is wrapped about the cigarettes and folded, but not sealed, at the ends of the cigarettes; (2) a “soft” or “hard” paper or paperboard package which is usually imprinted with brand specific information; and (3) an exterior clear overwrap of a heat sealable polymeric film polymeric film which is heat sealed.
A strip of polymeric material known as a “tear tape” is provided for easy opening of the polymeric overwrap films. Exemplary tear tapes are disclosed in U.S. Pat. No. 4,717,017 to Sprinkel, Jr. et al.; U.S. Pat. No. 4,836,378 to Lephardt; U.S. Pat. No. 5,192,262 to Amendola et al.; U.S. Pat. No. 5,595,803 to May et al.; U.S. Pat. No. 6,363,691 to Flaherty; and U.S. Pat. No. 7,118,792 to Hewitt et al., each of which is incorporated herein by reference. The tear tape typically is positioned adjacent and parallel to the top edge of the package. One end of the tear tape normally projects slightly from the package as a tab. To open the package, the tab is pulled by the smoker to open the polymeric overwrap. In particular, the projecting tab of the tear tape is pulled to slit the polymeric overwrap along both edges of the tear tape and the polymeric overwrap covering the top of the container is removed. The top of the package is then opened, i.e., the foil inner liner is torn open in the case of the soft pack or the hinged lid of the hard pack is pivoted open and a portion of the foil inner liner is removed to expose the ends of the cigarettes contained therein. The smoker then grasps the end, usually the filter end, of a cigarette with his/her fingers to remove it from the package.
Typically, the polymeric overwrap material comprises an oriented polypropylene which may be (a) a heat seal modified oriented polypropylene, (b) an acrylic heat seal coated polypropylene, or (c) a coextruded ABA type oriented polypropylene film wherein the A layers are fusion heat sealable polypropylene/polyethylene copolymer and the B layer is an oriented homopolymer of polypropylene. The composition of the heat seal layers is selected to optimize the heat sealing characteristics of the overwrap, i.e., the lowest practicable heat seal temperature and the shortest practicable dwell time. At the same time, however, the heat seal layer of the overwrap normally provides the necessary slip or antistick characteristics so that overwrapped cigarette packages readily slip or slide relative to one another during the manufacturing process and during dispensing of the cigarette packages, for example, for a cigarette vending machine. Accordingly, selection of the heat seal layer composition is essentially a trade off between optimum heat seal characteristics and optimum slip characteristics.
Under normal storage conditions and normal shelf life, the conventional cigarette package described above is capable of maintaining the freshness and moisture content of the cigarettes at an acceptable level for a limited period of time. However, if the cigarette packages are exposed to a longer than normal shelf life, or if the cigarette packages are stored in unusually hot and/or dry atmospheric conditions, the conventional package does not adequately preserve the freshness and moisture content of the cigarettes. In particular, the foil inner liner of the conventional cigarette package has a primarily decorative purpose inasmuch as the paper-backed foil liner is only overlapped at its longitudinal seam and folded over on the top and bottom of the package without sealing. Thus, the foil inner liner provides little or no barrier to the passage of oxygen and moisture between the cigarettes in the pack and the surrounding atmosphere. While the barrier effectiveness of the conventional heat sealed polypropylene overwrap is significantly greater than the conventional foil inner liner, the conventional overwrap does permit loss of moisture and flavor over a period of weeks so that the consumer can ascertain a change in the freshness of the product. If an extended shelf life or storage under adverse temperature and humidity conditions is encountered, there can result a staleness of the tobacco, a moisture loss, and a loss of tobacco flavor or aroma, including a loss of flavor additives, such as menthol.
Various packaging overwraps and inner liners have been proposed for improving the barrier properties of cigarette packages. For example, U.S. Pat. No. 3,948,389 to Molins et al. discloses an air impervious inner liner for a cigarette package wherein an air impervious tube is sealed flat with the resulting margin and triangulated ends being folded against the packet. Because of the resulting unusual end flap structure, the packages cannot be sealed by current cigarette package manufacturing equipment. U.S. Pat. No. 4,375,260 to Focke et al. discloses a laminated foil inner liner which, as in the case of the aforementioned Molins et al. patent, has an unusual end flap structure and cannot therefore be made by conventional cigarette packaging equipment. In addition, the Focke et al. inner liner has an easy opening preperforated feature which can result in severing of the impervious foil layer thereby reducing the barrier properties of the inner liner. U.S. Pat. No. 4,807,745 to Langley et al. discloses a barrier heat sealed package for cigarettes. The package material comprises a relatively thick laminate made of a foil layer to which two layers of biaxially oriented polypropylene homopolymer are adhesively bonded on opposite sides and exterior and interior surface layers of a heat sealable thermoplastic polymer are applied. This laminate is disclosed as being useful as an overwrap for a soft or hard pack or as a sealed inner liner for a soft or hard pack. Other overwrap materials known in the art include those with tamper-evident properties (e.g., U.S. Pat. No. 4,911,302 to Butler), aroma-releasing properties (U.S. Pat. No. 5,938,018 to Keaveney et al.)
It would be desirable to provide a heat sealable high barrier cigarette package overwrap or a cigarette carton overwrap of a gauge equal to or less than that of the conventional polypropylene overwrap for packages and export cartons. Such as overwrap desirably would preserve the freshness and moisture content of the cigarettes contained in the package or carton, thus, minimizing changes which might be detected by the consumer after passage of the normal period of time between cigarette manufacture and consumption. In addition, such as overwrap could increase the normal shelf life of the cigarettes or maintain a shelf life equal to or greater than normal shelf life under the most adverse storage conditions. Advantageously, such a cigarette package or carton would also be compatible with existing cigarette manufacturing and packaging equipment to the extent that major modifications of that equipment are not required to maintain production rates at least equal to present rates of cigarette package and carton production. In addition, it would be desirable to provide a high barrier cigarette package that has an external appearance at least comparable to conventional cigarette packages and also that may be opened in the same way as a conventional cigarette package. It would also be desirable to provide a high barrier cigarette package that has slip characteristics equivalent to or better than conventional cigarette packages.
These packages may include a laminate packaging component for barrier-sealed cigarettes including a foil layer, such as is described in U.S. Pat. No. 4,807,745 to Langley, and/or an outer film wrap of a type described by in U.S. Pat. No. 5,542,529 to Hein, each of which is incorporated herein by reference. Various modifications have been proposed to different cigarette package designs to enhance consumer acceptance and appreciation of the look and feel of a package. For example, it has been disclosed to round off the portions of a hard pack leading to the corners of the package to yield a “pillow-type” cigarette package, such has been disclosed in U.S. Pat. No. 6,694,708 to Brizzi et al. which is incorporated herein by reference. Alternatively, it has been disclosed to provide multiple methods of accessing the cigarettes. For example, U.S. Pat. No. 5,682,986 to Cobler, U.S. Pat. No. 5,139,140 to Burrows et al., and U.S. Pat. No. 5,248,031 to Burrows et al., each of which is incorporated herein by reference, disclose a removable portion of the lid of a hard-pack thereby providing for soft-pack style accessibility in addition to the hard-pack flip-top.
Modified atmosphere packaging has been introduced for a number of different products, including food products (see., e.g., U.S. Pat. No. 6,256,905 to White) and smokeless tobacco products (see, e.g., U.S. Pub. Pat. Apps. 2008/0029117 to Mua, et al. and 2008/0173317 to Robinson, et al., each of which is incorporated herein by reference). Single-pack, small-batch pack, and multipack cigarette containers with a modified internal atmosphere have been attempted, but each such package includes structural limitations that generally have prevented maintaining the appearance of a standard cigarette package with which most consumers are most familiar. See, for example, U.S. Pat. No. 5,729,957 to Spada and PCT App. Pub. Nos. 96/14763 to Brown et al.; WO01/83326 to {hacek over (S)}rámek et al.; and WO06/32661 to Weiss et al., which show modified atmosphere containers having a non-traditional cigarette pack shape. Other examples of non-conventional packaging shapes for smoking articles include U.S. Pat. No. 1,886,115 to Müller; U.S. Pat. No. 3,967,730 to Driscoll.
It is desirable to develop more attractive packaging for cigarettes, providing both visual and tactile attractiveness for consumers. In addition, it is desirable to provide packaging that communicates product quality and freshness.